The present invention relates generally to electrical insulators, and more specifically to an insulation configuration for use with high voltage switches which provides high voltage holdoff characteristics.
Modern lasers, electron beam projectors and accelerators possess switching requirements that include the need for insulators with holdoff capabilities exceeding voltages of 100 kV and currents exceeding of 100 kA. In the past, people have used large (up to eight inches) diameter ceramic cylinders along with hollow rectangular insulators made of plastic. In such prior art systems, current scaling was achieved by simply increasing the switch length, but this solution imposes severe constraints on the manufacture of insulators to provide long (up to several meters) switches which maintain their mechanical integrity while providing high voltage holdoff characteristics.
The task of providing high voltage insulators for long linear switches is alleviated, to some degree, by the following U.S. Patents, the disclosure of which are incorporated by reference:
U.S. Pat. No. 3,267,204 issued to D. Peters; PA1 U.S. Pat. No. 3,880,194 issued to W. McNeal; PA1 U.S. Pat. No. 3,673,305 issued to Mashikian et al; PA1 U.S. Pat. No. 4,177,322 issued to Homan, et al; PA1 U.S. Pat. No. 3,582,586 issued to P. Jones; PA1 U.S. Pat. No. 4,223,071 issued to Boyer et al; and PA1 U.S. Pat. No. 4,069,357 issued to Miller et al. PA1 U.S. Pat. Nos. 3,267,204; 3,880,194; 3,673,305; and 4,177,322 each disclose an insulator used in high voltage electrical applications.
U.S Pat. No. 3,582,586 discloses an arc-interrupting composition for the walls of electrical interrupting devices to improve the characteristics of such devices for interrupting high power circuits. The composition comprises melamine, and a thermoplastic organic binder. U.S. Pat. No. 4,223,071 discloses a high voltage insulating composition which includes phosphorus-containing compounds. U.S. Pat. No. 4,069,357 discloses a method for diffusing a coating of manganese powder and titanium powder into a ceramic to improve voltage holdoff withstanding capability.
The above-cited patents are exemplary in the art, and further demonstrate the attention being paid to the need to provide an insulation system for high voltage switches which have high voltage holdoff characteristics. The present invention is intended to satisfy that need.